Lubricating composition



m sses Met. 7, 1939 UNETEEB STATES greases auassoams semesters:

@sri F. Pruttori, Lieveland, @liio, assignor, by

means -nta, to The Lnbrl-Zcl Development Gorporation, meveland, Ohio, a corporation of Delaware No Drawing.

Application August 17, 1938,

Serial N0. 98,537

14 Claims.

This invention relates, as indicated, to lubricating compositions, and more particularly to compositions for use in connection with the lubrication of the working parts of internal combustion 5 engines, motor vehicles, etc., and it is among the objectsof this invention to provide compositions obviating the disadvantages of the usual petroleum oils.

When in use, as in the crank-case of an auto- 30 mobile, for example, it is a well-known fact that oils deteriorate,.forming considerable quantities of gummy and semi-solid materials generally included by :the term "sludge. This "sludge" i thickens the oil, increases friction, lowering the general eficiency of the engine, and necessitates frequent drainage and replacement of the lubricant. In winter the passage of small amounts of gasoline into the crank-case of an engine often results in the precipitation of sludge materials which are particularly objectionable since they hinder lubrication of the engine on starting, causing undue wear and starting trouble. Obviously,

an oil which does not sludge. under such condigg tions, would be especially desirable for winter use.

The frequent oil changes necessary at all times of the year in order to keep an engine operating eiliciently and without danger of are a major source of expense and annoyance.

In It has been discovered that this sludge which forms in the lubricating oil on use contains two predominant components comprising (l) polymerized hydrocarbons and (2) more or less oxidized polymerized hydrocarbons. These com- 85 ponents act as cementing agents for small particles of inorganic and insoluble materials, greatly impairing the lubricating effect of the oil. I have found that the best solvents for one component of the "sludge" are not the best for the other. For

addition to a lubricating oil it is obvious that solvents must be found which are mutually compatible, soluble or miscible in the oil, and which will J I dissolve the two components of the sludge" pre viously referred to. By lubricating oils are meant mineral oils or their synthetic equivalents.

pressure.

It is, therefore, among the objects of this invention to provide a lubricant which will not lose its lubricating qualities and suffer other deterioration due to "sludge" formation.

Another object of this invention is to provide a 5 lubricating composition which will not lose its lubricating qualities due to "sludge formation and will also have extreme pressure characteristics.

It is also among the objects of this inv tion to provide a lubricating mineral oil which will not deteriorate due to sludge formation and which will be especially effective under conditions of extreme Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly 2 pointed out in the claims.

The following description sets forth in detail certain approved combinations of ingredients embodying my invention, such disclosed means constituting, however, but certain of various forms in which the principle of the invention may be used.

Broadly stated, this invention comprises incorporating at least one each of a halogenated oxygen-free organic compound and an oxygenbearing organic compound, which is also preferably halogenated, with an 011 base.

As is hereinafter more particularly pointed out, the above defined components of the lubricant comprising thisv invention will preferably and for best results have certain physical and chemical characteristics which especially adapt the same for use in conjunction with the principal types of engines in use today, and for other uses.

The solvent components of the lubricant should be of fairly low volatility, i. e., with a vapor pres- 40 sure at a temperature of C. of below atmospheric, or preferably a vapor pressure less than atmospheric at a temperature oi C. In one embodiment of my invention now in commercial use, one component of my new solvent has a vapor little below atmospheric at 350 C., has proven highly satisfactory.

, Oz'wen free component I have found that of the entire class of halogenated oxyzen-free organic compounds usable as a component of the solvent constituent in my new lubricant, as above defined, the halogenated by drocarbons and generally those of the aromatic series are most highly desirable as solvents for the unoxidized polymerized hydrocarbon deposit; Throughout this application the term "aromatic series" is intended to include homologs as well. As hereinafter pointed out, however, certain of 2 the aliphatic compounds of this type are particularly useful for certain purposes.

In the case oi the halogenated aromatic oxygenfree compounds, it is preferable that the halogen be attached to a carbon atom of the benzenoid ring. These latter compounds are usually more desirable because of their non-corrosive character and general stability.

The halogenated oxygen-free organic compounds as noted may be either:

A. Aliphatic, such as halogenated:

I. Hydrocarbons,

Notably, those containing from four to ten carbon atoms, e. g. fluorinated hexane, iiuorinated octane, and fluorinated decane.

II. Amines Primary, secondary and tertiary, e. g. 40 hexylamines, diamylamines, tri-amylamines, such as: fluorinated tri-amyl amine, fluorinated hexyl amines; also: fluorinated tributyl amine,

or the more generally preferable:

B. Cyclic compounds, such as halogenated:

' I. Benzene and related compoimds such as:

(l) Halogenated benzene, e. g. the dichlorbenzenes, notably the ortho compound, the ortho-dibrom benzenes, and

the iluorinated benzenes.

. (b) Halogenated amino derivatives.

of benzene, e. g. chlorinate aniline, mono-chlor aniline (preferably the ortho-compound) mono-chlor iii-methyl aniline, chlorinated 7o toluidines, chlorinated xylidines,

' and chlorinated diphenylamine.

(c) Halogenated hydrobenzenes, e. g. hydrogenated dichlor-benrenes, dlchlorhexahydrobenzene (dichlor phenyl, e. g., chlorinated phenyl- .toluenes.

(b) Haiogenated amino derivatives of diphenyl, e. g. chlorinated phenyl-anilines, chlorinated phenyltoluidines, and chlorinated diphenyl amine.

(c) Halogenated hydrodiphenyls,

e. g. chlorinated phenyl hexahydrobenzene, and chlorinated dodecahydrodiphenyl.

thalenes, e. g. chlorinated methyl naphthalene, notably the alpha compound, chlorinated propyl, and isopropyl substitution products of naphthalene.

(b) Halogenated amine derivatives of naphthalene, e. g. chlorinated naphthylamines, and mono-chlor a-rnaphthyl amine.

(c) Halogenated hydronaphthalenes,

e. g. chlorinated decahydronaphthalene.

pyl and isopropyl derivatives of anthracene. I

(b) Ha'logenatedamine derivatives,

- e. g. chlorinated phenanthrylamines, and chlorinated anthramines.

(c) Halosenated 'threnes and halogenated hydroanthracenes, e. g., -chlorinated retene oil (contains hydro retene).

IV. Phenanthrene and anthracene and related compounds, such as:

(1) Chlorinated phenanthrene, chlorinated anthracene. (2) Hslogenated derivatives of phenan threne and anthraeene, such as:

hydrophenan- V. Chrysene, picene, and related compounds,

including their derivatives, such as homelogs, amine derivatives and other substitution products. 7.

VI. Bridged ring compounds, such as the terpenes and related compounds, and their derivatives, e. g. chlorinated pinene.

Heterocyclic compounds, such as pyridine, ouinoline, pyrrole, thiophene, and derivatives of them, e. g. mono-chlor pyridine.

It will be noted that the above enumerated examples of the organic ring compounds which are usually preferred are, in general, compounds of the aryl type, i. e., compounds containing As a matter of convenience, the halogenated diphenyls and substituted diphenyls, as well as halogenated substituted benzenes where two or more phenyl groups are directly linked, may be inclusively referred to as halogenated poiyphenyls.

Some of the best examplesoi the aromatic solvents are:

Chlorinated benzene, E-I. (l) e. g. di-chlor benzene (notably the ortho compound).

Mono-chlor toluene, B-i. (2) (a).

Qhlcrinated ethyl benzene.

Ghlorinatcd diphenyi id-H. (i)

Chlorinated aniline (2) (h).

Chlorinated pyridine E VM.

Chlorinated quirioline la-Vii.

Good examples of halogenated aliphatic hydrocarbons are:

Fiuorinated pentane.

f-luorluated hexane.

Fluoriuated octane.

Ealogeuated petroleum derivatives, particularly halogenated petroleum wanes.

ficycen hcavdag component i. have found that of the entire class of oxygenbearlue creme compounds usable as a component in my improved solvent as above defined the halogenated compounds and preferably those oi. the aromatic series are generally suor solvents for the ouidiam polymerized hycarbon deposit, and that these solvents may be used in conjunction with the solvents for the unoxidized polyme hydrocarbon deposit, also being compatible with the oil. Here again compounds of the arctic series with the halogen attached to the ring are favored. However, a certain num= ber of the orwgembearing aliphatic compounds have been found to be very effective,

The oxygen-bearing components may, for convenience, be sled as follows:

I. Aliphatic, or wrbcn chain t.

Oxygen-bearing derivatives of:

A. Hydrocarbons of the paramn series; B. Hydrocarbons oi the oleidne series;

and C. Hydrocarbons of the acetylene series.

II. Organic ring type.

Oxygen-bearing derivatives of A. Carbon ring" type compounds.

() 0! the aromatic, or allied type,

including ongen-bearing derivatives of benzene, naphthalene, an-

thracene, etc., also compounds of the bridged ring type such as the terpenes, and related compounds.

(b) O! the class including the cycloparafiins, cyclo-olefines, etc. Examples of this class are oxygenbearing derivatives of the following':

(1) Hydrogenation products of benzene (e. g. cyclohexane, cyclohexene, cyclohexadione), such as hydrogenated phenol notably cyclohexanol, di-hydro phenol, tetra-hydro phenol.

(2) Hydrogenation products of naphthalene (e. g., decahydronaphthalene, tetrahydronaphthalene, etc.), such as the hydrogenated naphthols.

(3) Naphthenes, such as naphthenic acid, etc.

(o) Oi mixed type such as derivatives of 'indene, hydrindene, hydranthracene, etc.

B. Heterogeneous ring pounds.

(a) Oi the aromatic or allied type including derivatives of pyridine, ouiuoline, etc.

(b) @ther types such as furan and its derivatives and derivatives of thiophene, pyrrole, etc.

type com- The oxygen hearing derivatives oi the foregoing compounds may also be classified according to the nature of the attachment of the oxygen to the molecule, vla.:-

I. Directly attached to one or more carbon atems, as in the case of: (1') and analogous compounds.

(2') Compounds containing the i:' -OH radlcie, such as alcohols and other derivatives oi carblnol (including phenois, cresols, naphthols, etc). (3') Compounds containing the carbonyl radicle, such as aldehydes, ketones, organic acids, esters and salts of organic acids, thio-acids and esters of Thefollowing table indicates some of the compounds which are especially suitable, halogenated or unhalogenated. as .the case may be:

Organic oxygen compounds Ring compounds Unhalogenated 'Halogensted Aromatic phenols Phenol o-Chior enol u-naphthol Moncch ora-naphthol Amino enols Butyl enol Phony phone] o u wa (W ably refined by distillation) I Alcohols Bensyl alcohol Ohlor bensyi alcohols Phcnyi ethyl alcohol Aldehydes (10m Bensaldehyde desira o cause ymerin l Ketonee Benso enone Mono-chlor bcnsophen- Phony tolylketones one Dinaphth lketonc Amides Acctaniii e Stearanilide Acids Phenyl fatty acids, Chlorphenyl acetic acid a. phenyl acetic ac Salicylic acid Chlor-sallcyllc acid Eaters Pheuyl acetate Ethyl chiorbensoates Phen lcarbonate Butyichlorbeusoates Ethy bensoate Di-ethyl chlorphthalates Butyl benscate l Dibutyl chlorphthalstes Diethylphthslatc Ethyl and butyl esters Dibutylphthalate oi chlorpbenyl acetic yl and butyl acid esters of yl acetic acid Methyl salicylate Methuuohlor aalicylates Bcnsglacetaie Chlor ylaeetatea Pyri ine acetate guinolinc accta lthsrs iphenyl other Chlfl dippenyl e Phenylethylethe'r Chlorphenyl athyl others Dlxenylcther Chlorinated .dixanyl n, Dinaphthyl other (32%!!! dinaphthyl Aik laied diphenyl Alkylated chlor diphenother yl ether Non-aromatic pounds oxygen bearing organic ring com- Cyclo-hexanol Naphthenic acids Esters of naphthenic acids Oxygen-bearing heterocyclic compounds (1) Furane, and

of pyromucic and pyrrole, e. g. carboxylic acids and esters of pyrrole carboxylic acids.-

esters of thiophene Chain compounds Unhaloscnated Halogenated Alcohols Hydroxy-emincs Ethers Ketones Acids Octyl alcohol Decyl alcohol Lsuryl alcohol Cetyl alcohol Methyl steanite Lauryl acetate p to Tri-ethanol amine 'Iri-butancl amino Butyl ether Amyl ether -Di-octy1 ketone Propionic acid Bntyric acid Laurie acid Flucrinated ootyl alcohol aloo-.

- Fluorinated decyi hoi Flgiarinatsd lauryl niece Fluorineted oetyl alcohol Methyl dicnior stearate bearing class is chlorinated diphenyl ether, con

taining an average of from about three to about eight atoms of halogen per molecule. Chlorinated diphenyl ether which contains about six atoms of'chlorine per molecule, and has preferably been purified by vacuum distillation, or other means, is one of the most desirable solvents of this class. This solvent boils at a temperature'above 300 C. without appreciable decomposition. (Bee my co-pending application Ber. No. 83,976.)

or the above enumerated classes of oxygen: bearing compounds, the aromatic compounds are generally preferred and particularly the arcmatio ethers and ketones. Another preferred class of compounds is that in which oxygen forms a part of a ring structure. In the case of unhalogenated oxygen-bearing organic compounds they should boil at atmospheric pressure without appreciable decomposition.

Since aromatic compounds containing multiple ring structures of the condensed type such as naphthalene, anthracene, penanthranene, etc.

(that is, of the type in which certain carbon atoms are contained in or common to two rings) are more easily oxidized, and, therefore, less stable than the non-condensed" multiple-ring game radicle, have the additional advantage of "inhibiting corrosion, and therefore otherwise corrosive halogenated oxygen-free organic compounds may be used'in conjunction with them for service in lubricants. Notable examples of such compounds are the organic phosphates, of which tri-cresyl phosphate is a good example,

and the phosphites, such as tri-phenyl phosphite.

However, with these exceptions the. oxygen is generally preferred on .the form of an organic radicle.

Preferred combinations to make up my new v solvent include: about 2 5% to 75% o-dichlor benzene with one or more of the following:

The chlorinated oiplicnyi oxide compounds re ferred to above are compounds contnining an average number of chlorine eouivelent to that indicated.

Chlorine, bromine, and fluorine are the halogens most desirable in both the oxygen-free and oxygen-containing compounds, fluorine forming particularly stable compounds which are no longer so diflicult to prepare us formerlyl Methods of reparing fluorine compounds which will be found satisfactory for use in my solvent are described. Zor instance, in U. 8. Patent No. 2,013,030, Exampie IV, and in U. S. Patent No. 2,013,050, Exampie X. My invention, of course, is not to be considered as involving any particular method preparation of the components nor is it intended to be limited by any such method or methods. Chlorine is the least expensive and most commercially available of all the halogens, and bromine is also satisfactory, although considerably more expensive, as is iodine.

As the exact manner in which my solvent constituents act upon the sludge is not entirely understood, I do not intend my invention to be restricted by any explanation or theory. However, it seems that the two types of solvents mutually aid one another in attacking the gummy s1udge" for it has been found that the eflective' ness of their joint action is more than the cumu' lative efiect of the two when used separately The presence of the halogen lowers the volatility and thus enables the use of a number of the most efiective solvents which would otherwise be too highly volatile at engine temperatures. The presence or the halogen also notably enhances the solvent action of the compounds and there fore makes available more eflective compounds. The degree of halogenation may, however, reach an optimum beyond which further halogenation gives no improvement in the solvent action or may even cause a decline in efi'ectiveness.

The solvent action of my new lubricant may sometimes be improved by the use of a more or less complex mixture of one or both of the two solvent addition components used. This complexity may result irom (a) the production or a plurality of compounds obtained by the halogena=' tion process, as, for example, the chlorination oi diphenyl which is capable of producing a large number of chlorine bearing compounds difiering as to the number and location or the chlorine atoms in the molecule; or (b) the use of a prod= uct resulting from the halogenation of a complex organic material such as certain still fractions and solvent-extraction fractions obtained in the acne. ration oi petroleum products and coaltar products.

gen-free organic constituents and oxygen-bearing organic constituents in the new solvent comprising my invention may vary within wide limits, depending upon the particular materials used, a very minor proportion of the more active com ponents at times being quite efiective, the mud oi oil to which the solvent is to be added, and the mud of engine employing the lubricant. The ratio of the amount of halogenated oxygen-free organic constituents to the amount of oxygenbearing organic material usually may vary from about one to ten, up to about ten to one, but preferably only from about one to two, up to'two to one. For most applications a lubricating composition containing a solvent comprising substantially equal amounts of each type has been round very satisfactory.

The amount of the solvent combination to be added to the oil will depend upon the type of oil and the type of engine using the lubricant, and may vary over wide limits, for example, from factor.

about .001% to about 20% by weight based on the oil. To obtain a maximum of desirable characteristics in the lubricant, a proportion-o! from about .1% to about 3% of the combined solvent is usually of advantage while amounts up to 5 or are occasionally desirable and amounts up to may often be used without unduly decreasing the viscosity of the lubricant.

Proper stability of the components of the solvent combination in the lubricant is an important Since the materials are to be exposed to relatively high temperatures in the crank-case, etc., they should be particularly resistant to thermal decomposition.

Resistance to hydrolysis is a most desirable characteristic because of the likelihood of a certain amount of moisture being present in the crank-case. Under these conditions; easily hydrolyzed halogen compounds will tendto produce hydrogen halides which will cause corrosion of the parts of the engine with which they come in contact.

The superiority of my lubricant has been demonstrated commercially by its highly successful use in automobile, truck and bus engines. The solvent constituents may be most conveniently introduced into the mineral oil before such oil is placed in the crank-case, but this invention does not cover nor is it intended to be limited by any particular method of addition oi the solvent constituzents to the lubricant. Any practicable means of addition is intended to be within the scope of this invention. Uther specific applications of this invention have been made and will occur to those acquainted withthe art and this invention is intended to include all such applicatlons.

To a mineral oil base are therefore added my solvent constituents comprising at least one representative or each of the two types of compounds disclosed to inhibit the formation and aid in re moval of oil sludge. It is distinctly preferable, but not absolutely necessary, that at least one or the solvents be of the aromatic series. The two solvent compositions described have a coo eratlve dissolving enact, each enabling the other to work more quickly and completely.

invention is equally applicable to other than automotive fields of lubrication and other uses for my improved lubricant will be immecliately apparent to those skilled in the art. This invention is intended to cover all such applications.

it is also to be noted that combinations of the type described are highly effective in increasing the extreme pressure characteristics oi the lubricant, and thus my improved lubricant has the combined advantages of being non-sludging, even in cold weather, and at the same time proriding the safety of an extreme pressure lubricant.

This application'is a continuation in part of my copending applications Ser. Nos. 737,070, filed July 26, 1934, and 755,987, filed December 4, 1934.

Other modes of applying the principle of my invention may be employed instead 0! the one explained, change being made as regards the materials employed in carrying out the process, provided the ingredient or ingredients stated in any of the following claims or the equivalent of such stated ingredient or ingredients be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A lubricating composition containing as a principal lubricating constituent a major amount such composition ailfecting its use as a lubricant improved by incorporating therein a total amount of at least .l%, based on the amount of mineral oil, of both an oil-soluble halogenated oxygeniree aromaticcompound and an oil-soluble organic oxygen compound, the proportion of each orsaid compounds being less than based on the amount of said mineral lubricating oil and said compounds being oi the type which will not substantially evaporate from such lubricating composition at ordinary temperatures.

2. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition affecting its use as a lubricant improved by incorporating therein a total amount of at least .l%, based on the amount of mineral oil, of both, an oil-soluble chlorinated aromatic hydrocarbon and an oil-soluble saponiflable organic oxygen compound, the proportion oi each of said compounds being less than 20% based on the amount of said mineral lubricating oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temperatures. 1

3. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition airecting its use as a lubricant improved by incorporating therein a total amount of at least .i%, based on the amount of mineral oil, of both an oil-soluble halogenated oxygenfree organic ring compound and an oil-soluble saponiilable organic oxygen compound. the pro-.

. of mineral lubricating oil with the properties of such composition aflecting its use as a. lubricant improved by incorporating therein a total amount of at least .1%, based on the amount of mineral oil, of both an oil-soluble halogenated oxygeniree aromatic compound and a stable oil-soluble saturated organic oxygen compound, the proportion of each oi said compounds being less than 20% based on the'amount of said mineral lubricating oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temper:

atures.

5. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition affecting its use as a lubricant improved by incorporating therein a total amount of at least .1%, based on the amount of mineral oil, of both an oil-soluble chlorine bearing oxygen-free substituted benzeneand an oil-soluble organic oxygen compound, the proportion of each of said compounds being. less than 20% based on the amount of said mineral lubricating oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temperatures.

6. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the propertiesoi such composition aiIecting its use as a lubricant improved by incorporating therein a total amount of at least .1%. based on the amount of mineral of mineral lubricating oil with the properties ofoil, oi both a chlorinated benzene and an oilsoluble organic oxygen compound. the proportion of each 01 said compounds being less than 20% based on the amount of said mineral lubricating oil and said compounds being of the type which will not substantially evaporateirom such lubricating composition at ordinary temperatures.

7. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition ail'ecting its use as a lubricant improved by incorporating therein a total amount of at least .1%, based on the amount of mineral oil, of both ortho-dichlorbenzene and an oil-soluble organic oxygen compound, the proportionof each of said compounds being less than 20% based on the amount oi said mineral lubricating oil and said compounds being 01 the type which will not substantially evaporate from such lubricating composition at ordinary temperatures.

8. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition aflecting its use as a lubricant improved by incorporating therein a total amount oi at least .1%, based on the amount of mineral oil, of both an oil-soluble halogenated oxygeniree organic ring compound and halogenated diphenyl oxide, the proportion of each of said compounds being less than 20% based on the amount of said mineral lubricating oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temperatures. a

9. A lubricating composition containing as a principal lubricating constituent a majoramount or mineral lubricating oil with the properties of such composition aifecting its use as a lubricant improved. by incorporating therein a total amount of at least .l%, based on the amount of mineral oil, 'of both ortho-dichlorbenzene and chlorinated diphenyl oxide, the total proportion of said compounds being within their combined solubility in said mineral lubricating oil.

10. A lubricating composition containing as a principal lubricating constituent a major amount oi mineral lubricating'oil with the properties of such composition affecting its use as a lubricant in the crank case 01' an internal combustion engine improved by incorporating therein a total amount or at least .l%,'based on the amount of mineral oil, of both a stable oil-soluble halogenated oxygen-free aromatic compound and a stable oil-soluble organic oxygen compound, the proportion of each oi said compounds being less than 20% based on the amount of said mineral lubricating oil and said compounds having a vapor pressure below atmospheric at a temperature of C.

11. A lubricating composition containing as a principal lubricating constituent a major amount oi mineral lubricating oil with the properties of such composition afl'ecting its use as a lubricant in the crank case of an internal combustion engine improved by incorporating therein a total amount of at least .1%, based on the amount of mineral oil, oi both a stable oil-soluble halogenated organic compound and a stable oil-soluble oxygen-free aromatic oxygen compound, the proportion of each of said compounds being less than 20% based on the amount oi said mineral lubricating oil and said compounds having a vapor pressure below atmospheric at a temperature of C. 12. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil, the sludge solventicity of which is improved by incorporating therein an effective minor amount of both an oil-soluble 5 halogenated oxygen-free aromatic compound and an oil-soluble organic oxygen compound, the proportion of each of saidcompounds being within their combined solubility in said mineral lubricating oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temperatures.

13. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition aflecting its use as a lubricant improved by incorporating therein a total amount of at least 2.1%, based on the amount of mineral oil, of both an oil-soluble halogen bearing oxygen-free aromatic ,compound and an oil-soluble organic oxygen compound, the total proportion of canon-roars Patent no. 2 15o,o79i

each of said compounds being less than 5%. based on the amount of mineral oil, the ratio of the amounts of said compounds being irom about 1 to 10, up to about 10 to 1, and said compounds being of the type which will not substantially 5 evaporate from such lubricating composition at ordinary temperatures.

14. A lubricating composition containing as a principal lubricating constituent a major amount of mineral lubricating oil with the properties of such composition aflfecting its use as a lubricant improved by incorporating therein a total amount of at least .l%. based on the amount 01 mineral oil, of both an oil soluble halogen hearing oxygenfree aromatic compound and an oil-soluble ester. the total proportion of each of said compounds being less than 20%, based on the amount of mineral oil and said compounds being of the type which will not substantially evaporate from such lubricating composition at ordinary temperatures.

' CARL F. PRUI'ION.

0F co sEcTIoN;

, March 79 939 CARL F PRUTTON It is hereby certified that error a pears in the printed specification of the above numbered patent rewiring correction as follows: Page 5 first column, line 1 1, for "B-VIII" read B-VIl; page 6,

first column, line 55, claim 5, strike out the word "saponlfiable"; and second column, line 68, claim 11, for "organiic read oxygen-free aromatic; oxygen-free aromatic read organic; page'T, first column, lines line '69, same-claim, for 7 and 8s claim 12, for within their combined solubility in read le as t 20% based on the amount 01; and that the said Letters Patent should be read with this correction therein the Patent Officeo that the same may conform to the record of the case in Signed and sealed this 18th day of April, A. D 1 9590 Henry Van Arsdale acting Commissioner of Patents. 

